To hypothermically warm a patient, a convective warmer to which a warming blanket is connected is used. There are various convective warming blanket types that exist in the market today. The various blankets have different dimensions. Prior to the instant invention, a convective warmer, such as the current Level 1 Equator™ warmer, operates at only one speed, so that the same amount of air is output from the warmer irrespective of the size of the blanket connected to the warmer.
Insofar as the different blankets have different sizes, as for example from a full adult size blanket to a neonate blanket, and those blankets have different exhaust capabilities, the existing convective warmers such as for example the aforenoted Level 1 Equator™ system use differently sized outlet hoses adapted to mate with the differently sized blankets. For example, for a regular adult size blanket, a regular outlet hose is used. However, if the convective warmer were to be used to provide heated air to a pediatric warming blanket, which has a smaller dimension than a regular adult blanket, a special hose has to be fitted to the convective warmer so that a portion of the heated air is either blocked or bypassed from the blanket. This is due to the fact that a full size adult blanket requires a higher air flow and thus more volume of air in order to be inflated with the proper pressure, with the heated air coming out of the various holes or slits from the blanket to warm the patient. On the other hand, for a smaller warming blanket such as for example a pediatric blanket, the same amount of air input to the blanket, if possible, will over inflate the blanket. As a result, to inflate the pediatric blanket, a different hose has to be configured for the outlet of the convective warmer to bypass a portion of the output air so that the pediatric blanket could be properly inflated, and the proper output of heated air provided to warm the child patient covered by the blanket.
In co-pending applications entitled “System for Providing Actuated Optimal Inflation to Multiple Temperature Regulated Blankets and Method Therefor” and “System for Providing Optimal Inflation to Multiple Temperature Regulated Blankets and Method Therefor”, both filed on Feb. 18, 2005 and assigned to the same assignee as the instant application, systems for inflating patient warming blankets of different dimensions at respective optimal flow rates are disclosed. The '0033 system requires the actuation of at least one switch for activating the system. In the '0034 systems, a sensor provided at the outlet at the system provides a feedback for controlling the flow rate of air to inflate the blanket. For such a feedback system, an expensive sensor, and an accompanying feedback circuit are required. The respective disclosures of the '0033 and the '0034 applications are incorporated herein by reference.
The present invention discloses a convective warmer that automatically inflates blankets of various dimensions optimally without requiring either switch actuation by a user or the expensive sensor and feedback system as disclosed in the above-referenced applications.